Such textile machines are known from state of the art. They can be, in particular, spinning machines, for example a rotor spinning machine or a winding machine.
The term “identical workstations” is understood as units capable of executing a defined work process simultaneously. It is obvious that during the operation of the textile machine, individual or several of the identical workstations are in another phase of the working process as the others. For example, some of the workstations can be in a production phase, others in a preparation phase of the production phase, and still others in a resting phase. Typically, the workstations are combined into sections, in which case one section can include 20 workstations, for example.
In spinning machines, this work process is typically a spinning process, i.e. a manufacturing process for a yarn that can include the winding of the yarn produced on a bobbin, for example a cross-wound bobbin; in winding machines, a winding process, i.e. a process for manufacturing a bobbin of pre-produced yarn. Usually, in textile machines, the workstations are arranged in each case beside one another along both longitudinal sides.
Each workstation has the essential components required for executing the work process. However, it is not necessary for the workstations to be absolutely identical. Thus, for example, individual workstations can be equipped with additional sensors for registering certain sizes that must be registered only once for several workstations.
Although textile machines in which the workstations are arranged along only one longitudinal side are conceivable, it is nonetheless usual to arrange the workstations beside each other along both longitudinal sides.
Typically, the workstations are combined in sections arranged between two terminal frames, from which the first terminal frame—also known as a operating frame—can include a central operating device and the other terminal frame—also known as a driving frame—can include central drives for the workstations.
It is furthermore customary for such textile machines to have many maintenance devices for servicing the workstations that can be moved along the work stations. The maintenance devices can be especially developed on the workstations for cleaning them and/or for repairing malfunctions, such as for repairing broken yarn, for example.
In order to allow the textile machine to operate and the work processes of the textile machine components to be operated, a control and communication system has been provided that typically includes a central control device connected to the central operating installation and that can be especially arranged in the operating frame. Likewise, the control and communication system can include a driving control device that controls the central drives and is usually arranged in the driving frame.
Apart from that, the control and communication can have a sectional control device for every section for controlling the respective section and, for each workstation, a workstation control device for controlling the respective workstation. It is furthermore also customary for each one of the maintenance devices to have a maintenance device control device.
Usually, the control and communication system includes one or several data buses that allow communication (i.e. data transfer) between the central control device, the sectional control devices, the workstation control devices, the maintenance device control devices and/or, if applicable, existing additional control devices.
Here, a data bus is generally understood to be a system for transferring data between several participants via a common transfer path, in which the participants do not participate in the data transfer between the other participants.
Generally, data buses consist of at least one physical bus line and the bus participants connected to it, also known as nodes, which in a generic textile machine can be the control devices mentioned above. Typically, the bus participants are connected to the respective bus line by means of the so-called IDC method of termination or plug systems without physically interrupting the bus line as a result of this.
Simpler data buses include merely an inner bus line to which all bus participants are connected. On each one of the two open ends, it is possible to place a terminal resistance to prevent reflections of the typically high-frequency electric signals.
So several bus lines can be physically coupled, it is customary to use bus topology components such as repeaters or bridges. As a result of this, data buses in tree or star topologies and/or with long stubs become possible. In addition, this method allows data bus systems that have several logically autonomous data buses to become possible.
Usually, data buses are developed in textile machines as a field bus, particularly as a CAN bus (controller area network bus) and often the CAN open bus protocol is used. The nodes, but also the bus topology components in particular, are developed so they support the respective protocol.
It is furthermore customary in generic textile machines that every one of the maintenance devices is connected to such a bus topology component through a physical maintenance device bus line, in which case at least some of the bus topology components are connected to a common bus line of the control and communication systems. As a result of this, a data exchange both among the maintenance devices themselves and with other nodes of the respective data bus is made possible.
The maximum length of the bus lines is inversely proportional to the bandwidth used in a data bus. As a rule, generic textile machines are manufactured with a variable number of sections depending on the order. In this case, there has been a need to increase the maximum number of sections for some time and with it the number of workstations. However, on the one hand, this causes an increase of the amount of data to be transferred by the communication system, which by itself would favor an increase of bandwidth, but on the other hand, the data bus lines also become physically longer owing to the increasingly long textile machines and this would suggest a lowering of the bandwidth. Known control and communication systems therefore limit the maximum number of sections or workstations of a generic textile machine.